Impact of glyphosate applied preharvest on oat kernel quality

Abstract

Background and objectives Preharvest glyphosate is applied to oats for weed control and as a desiccant. The effect of glyphosate applied at various stages of oat physiological maturity on oat end product quality has not been reported previously. In this study, the effects of glyphosate application at two separate stages of physiological maturity on oat groat quality and rolled oats quality were determined. Findings Oat was grown at two locations. Glyphosate was applied at the soft dough, physiological maturity stages, or not applied. Effect of preharvest glyphosate application at the oat soft dough stage on groat hardness, groat percentage (0.7%–3.7% decrease by cultivar), and percent plump groats (0.3%–6.1% decrease by cultivar), when compared to untreated oats, was noticeable. However, glyphosate applied at physiological maturity (manufacturer's recommendation) did not detrimentally affect groat starch (average 60.3%) or end product quality. Conclusions Therefore, from an end‐user perspective, applying glyphosate preharvest at oat physiological maturity does not impact oat quality. Significance and novelty Glyphosate when applied preharvest to oats can control weed and facilitate harvest, a boon to farmers. Final oat quality, a decisive factor for commercial processor use, was not detrimentally affected when glyphosate was applied at oat physiological maturity.